@Daojoan no tracking on RSS? You wish!

Aside from obvious tracking pixels there are somewhat smart ways: When hitting the subscribe URL do a 301 "Moved Permanently" redirect to a feed URL containing a custom ID, a "good" feed reader will then store that URL and then all links and media references can contain the ID to track. This won't track when exactly you read the feed content, but will track when embedded d images are loaded (smart people block that) or click on a link (to full article?)